Water-based paint for ceramic tiles, marbles and slabstones and preparation method of water-based paint

Abstract

The invention relates to the technical field of water-based paint, in particular to water-based paint used on ceramic tiles, marbles and stone slabs and a preparation method of the water-based paint, and the water-based paint comprises the following components in parts by weight: 55-75 parts of acrylic acid-silane modified copolymer emulsion; 3-8 parts of nano silicon dioxide sol; 2 to 6 parts of fluorine modified polyurethane dispersion; 0.1 to 0.5 part of a multiwalled carbon nanotube aqueous dispersion; 5-10 parts of a bio-based epoxy resin emulsion; 0.2 to 0.6 part of a defoaming agent; 0.5-1 part of a leveling agent; 0.3 to 0.6 part of a wetting agent; 3-8 parts of a coalescing agent; 0.4 to 1.2 parts of a thickening agent; 0.1 to 0.2 part of an anti-mildew bactericide; according to the present invention, the coating shows the super-strong comprehensive performance, the high adhesion is maintained, the excellent water resistance, the excellent chemical resistance, the excellent wear resistance and the excellent scratch resistance are achieved, and the comprehensive protection is provided for the surface of the inorganic base material.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of water-based coatings, in particular to a water-based coating for ceramic tiles, marbles and stone slabs and a preparation method thereof. BACKGROUND

[0002] In recent years, with the booming development of the building decoration industry, there is an increasing demand for the protection and beautification of the surface of inorganic substrates such as ceramic tiles, marbles and stone slabs. However, traditional water-based coatings face many challenges in their application on these materials. First, due to the smooth and dense surface of inorganic substrates, conventional water-based coatings have difficulty in forming good adhesion, leading to easy peeling of the coating. Second, these materials are often used in humid environments such as bathrooms and kitchens, which puts higher requirements on the water resistance and chemical resistance of the coating. Third, as decorative materials, the coating also needs to have excellent wear resistance, scratch resistance and self-cleaning properties to maintain long-term aesthetics.

[0003] In the prior art, some researchers have tried to improve the performance of coatings by modifying acrylic emulsion or adding inorganic fillers. For example, some studies have used silane coupling agents to modify acrylic emulsion to enhance the adhesion of the coating to the substrate. Some researchers have tried to add nano-silicon dioxide to improve the hardness and wear resistance of the coating. Some other studies have focused on improving the hydrophobicity and self-cleaning ability of the coating by introducing fluorinated components. However, these methods can only improve certain aspects of the performance of the coating, and it is difficult to meet the requirements of adhesion, water resistance, chemical resistance, wear resistance and self-cleaning ability at the same time.

[0004] In addition, with the increasing awareness of environmental protection, the coating industry is under pressure to reduce volatile organic compound (VOC) emissions. Traditional high-performance coatings often contain a large amount of organic solvents, which not only pollute the environment, but also may harm the health of construction workers and users. Therefore, it is an urgent need to develop a water-based coating with high performance and environmental friendliness. SUMMARY

[0005] The present application is precisely aimed at the above technical problems, and proposes an innovative water-based coating formula and a preparation method thereof. The coating realizes the synergistic effect between the components through careful design of the multi-component system, not only solving the application problems of traditional water-based coatings on inorganic substrates, but also making breakthrough progress in environmental friendliness.

[0006] The present application aims to provide a water-based paint for ceramic tiles, marble and stone slabs, which comprises the following components in parts by weight: 55-75 parts of acrylic-silane modified copolymer emulsion; 3-8 parts of nano-silica sol; 2-6 parts of fluorine-modified polyurethane dispersion; 0.1-0.5 parts of multi-walled carbon nanotube water dispersion; 5-10 parts of bio-based epoxy resin emulsion; 0.2-0.6 parts of defoaming agent; 0.5-1 part of leveling agent; 0.3-0.6 parts of wetting agent; 3-8 parts of film-forming aid; 0.4-1.2 parts of thickening agent; 0.1-0.2 parts of mildew-proof fungicide; and 20-30 parts of deionized water.

[0007] Specifically, the preparation method of the acrylic-silane modified copolymer emulsion comprises the following steps: (1) adding 150-180 g of deionized water in a four-necked flask and heating to 75-80°C under nitrogen protection; (2) mixing 45-55 g of acrylic acid and 5-10 g of 3-methacryloxypropyltrimethoxysilane; (3) dissolving 0.5-1.0 g of ammonium persulfate in 20-30 g of deionized water; (4) slowly adding the monomer mixture of step (2) into the reaction kettle under stirring at 300-400 rpm for 2-3 hours; (5) at the same time, slowly adding the initiator solution of step (3) for 2.5-3.5 hours; (6) after the reaction is completed, keeping the temperature at 75-80°C for 1 hour; (7) cooling to room temperature and adjusting the pH to 7.0-8.0 with 10% sodium hydroxide solution; (8) filtering through a 100 mesh sieve to obtain the final product.

[0008] 3. The water-based paint according to claim 1, wherein the preparation method of the multi-walled carbon nanotube water dispersion comprises the following steps: (1) adding 500-600 mL of deionized water in a beaker; (2) adding 1-2 g of sodium dodecylbenzenesulfonate as a dispersant and stirring until completely dissolved; (3) slowly adding 10-20 g of multi-walled carbon nanotube powder at a stirring speed of 400-500 rpm; (4) using a probe-type ultrasonic processor for ultrasonic dispersion, each treatment for 10 minutes, with an interval of 5 minutes, and the total treatment time being 60-90 minutes, and using an ice bath to control the temperature at 20-25°C during the treatment process; (5) filtering the dispersion through a 400 mesh sieve; (6) removing large agglomerates using a centrifuge (5000 rpm, 30 minutes); and (7) taking the supernatant as the final product.

[0009] 4. The water-based coating according to claim 1 is characterized in that the preparation method of the bio-based epoxy resin emulsion comprises the following steps: (1) adding 400-450g of epoxy soybean oil (epoxy value 5.8-6.2%) into a four-necked flask; (2) slowly adding 20-25g of polyethylene glycol monooleate and 5-8g of polyethylene glycol monolaurate as emulsifiers at 60-65°C, with a stirring speed of 300-400rpm; (3) slowly adding 450-500g of deionized water dropwise under continuous stirring for 30-40 minutes; (4) homogenizing using a high-speed shearing machine (10000-12000rpm) for 10-15 minutes; (5) cooling to room temperature and filtering through a 200-mesh sieve.

[0010] 5. The water-based paint according to claim 1, characterized in that: the nano-silica sol has a particle size of 20-25 nm, a solid content of 49-51%, and a pH of 8.5-9.5; the fluorine-modified polyurethane dispersion has a solid content of 38-42%, a pH of 7.0-9.0, and a viscosity of 50-800 mPa·s; the defoaming agent is a polydimethylsiloxane emulsion with a viscosity of 350-550 cSt and a specific gravity of 0.96-0.98; the leveling agent is a polyether-modified polysiloxane copolymer with a density of 1.01-1.02 g / cm 3 The wetting agent is sodium dodecylbenzenesulfonate, with an active substance content of ≥92% and a pH value of 6.0-8.0; the film-forming aid is dipropylene glycol butyl ether, with a boiling point of 230-232°C and a flash point of 100-102°C; the thickener is hydroxyethyl cellulose, with a 2% aqueous solution viscosity of 3400-5000mPa·s and a pH value of 6.0-8.5; the mildew and fungicide is an isothiazolinone mixture, with an active ingredient content of 1.3-1.7% and a pH value of 2.0-4.0.

[0011] 6. The preparation method of the water-based paint according to any one of claims 1-5, comprising the following steps: (1) pre-dispersion: adding 20-30 parts of deionized water into a reaction kettle, then adding a multi-walled carbon nanotube water dispersion and a nano-silica sol, stirring at a speed of 300-400 rpm for 10 minutes and 15 minutes respectively; (2) main emulsion addition: adding an acrylic-silane modified copolymer emulsion and a fluorine modified polyurethane dispersion into the reaction kettle under stirring, and the feeding time is 10-15 minutes; after the feeding is completed, continue to stir for 30 minutes; (3) functional component addition: adding a bio-based epoxy resin emulsion at 60-65°C, and then adding a film forming aid, a leveling agent, a defoaming agent, a wetting agent and a mildew-proof fungicide in sequence after the temperature is lowered to 40-45°C; (4) adjustment and homogenization: adding a thickening agent and deionized water at 35-40°C, and homogenizing for 10-15 minutes using a high-speed dispersion machine at a speed of 3000-4000 rpm; (5) vacuum degassing and filling: vacuum degassing for 15-20 minutes at -0.08 MPa, filtering through a 5 μm precision filter, and filling under nitrogen protection.

[0012] 7. The preparation method according to claim 6, wherein in the step (3), the components are added in the following order: first, the film forming aid is added and stirred for 5-10 minutes; then, the leveling agent is added and stirred for 5-10 minutes; then, the defoaming agent is added and stirred for 5-10 minutes; then, the wetting agent is added and stirred for 5-10 minutes; and finally, the mildew-proof fungicide is added and stirred for 10 minutes.

[0013] 8. The preparation method according to claim 6, wherein in the step (4), after the thickening agent is added, the stirring is continued for 20 minutes, then the deionized water is added, the stirring speed is increased to 500-600 rpm, and the stirring is continued for 30 minutes.

[0014] 9. The preparation method according to claim 6, wherein in the step (5), the filtered paint is filled into a clean and dry container under nitrogen protection, and is stored after being sealed.

[0015] 10. The water-based paint according to any one of claims 1-9, wherein the solid content of the water-based paint is 50-55%, the pH value is 7.5-8.5, the viscosity is 2500-3500 mPa·s, and the minimum film forming temperature is <0°C.

[0016] The core innovation of the present application is that:

[0017] 1. The acrylic-silane modified copolymer emulsion is introduced, and the silane groups in the molecular structure of the emulsion can form strong chemical bonding with inorganic substrates, thereby significantly improving the adhesion of the coating. Meanwhile, the introduction of the silane groups also increases the crosslinking density of the polymer chain, thereby improving the overall performance of the coating.

[0018] 2. The use of multi-walled carbon nanotube water dispersion takes advantage of its unique tubular structure and excellent mechanical properties to form a three-dimensional network structure in the coating. This structure not only greatly improves the wear resistance and scratch resistance of the coating, but also enhances the electrical conductivity of the coating, which helps prevent static electricity.

[0019] 3. The innovative use of bio-based epoxy resin emulsion not only reduces VOC emissions, but also provides a better cross-linked network through its special molecular structure. The introduction of this bio-based material significantly improves the environmental friendliness of the coating while maintaining high performance.

[0020] 4. The clever introduction of fluorine-modified polyurethane dispersion forms a low-surface-energy structure on the surface of the coating by using fluorinated components, achieving excellent hydrophobicity and self-cleaning ability. This design not only improves the practicality of the coating, but also extends its service life.

[0021] 5. The use of nano-silica sol forms an interpenetrating network structure with the polymer matrix, significantly improving the hardness and wear resistance of the coating. Nanoscale dispersion also ensures the transparency and gloss of the coating.

[0022] 6. The selection and amount of film-forming additives are optimized to solve the problem of difficult film formation of water-based coatings in low-temperature environments, expanding the application range and construction conditions of the coating.

[0023] The synergistic effect of these innovations makes the water-based coating of the present invention achieve a technological breakthrough in many aspects:

[0024] First, the coating exhibits super-strong comprehensive performance, maintaining high adhesion while achieving excellent water resistance, chemical resistance, wear resistance, and scratch resistance. This comprehensive performance improvement far exceeds the effect of single modification, providing all-round protection for the surface of inorganic substrates.

[0025] Second, the coating exhibits excellent self-cleaning ability with a stain removal rate of up to 98%. This feature not only greatly reduces daily maintenance costs, but also provides long-term protection for the appearance of the coating.

[0026] Third, the coating exhibits excellent UV aging resistance, which may be due to the synergistic effect of multi-walled carbon nanotubes and nano-silica, forming an effective UV shielding layer. This feature greatly extends the service life of the coating, especially suitable for outdoor or strong light environments.

[0027] More importantly, the present invention maintains a low VOC content while achieving the above-mentioned high performance. This breaks the traditional concept that high-performance coatings must be accompanied by high VOC content, providing a new idea for the sustainable development of the coating industry.

[0028] Finally, the coating shows a broad spectrum of applicability, which can be well performed on various inorganic substrates such as ceramic tiles, marbles and stone slabs. This broad spectrum of applicability greatly simplifies the material selection and construction process in practical applications.

[0029] In summary, the present application not only solves many problems of traditional water-based coatings in the application on inorganic substrates, but also makes breakthrough progress in environmental friendliness, self-cleaning ability, anti-aging property and the like. This all-round performance improvement opens up a new way for the development of high-performance water-based coatings, and has important theoretical significance and broad application prospect. The success of the present application will provide a high-performance, long-life, easy-to-maintain and environmentally friendly coating solution for the fields of building decoration, bathroom facilities, kitchen renovation and the like, and is expected to trigger technological innovation in the related industries. DETAILED DESCRIPTION

[0030] To make the objectives, technical solutions and advantages of the present application clearer, the technical solutions of the present application will be described clearly and completely below in combination with specific embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the scope of protection of the present application.

[0031] The coating of the present application, the particle size of the nanosilica sol is 20-25 nm, the solid content is 49-51%, the pH value is 8.5-9.5, the trade name is only TM-50; the solid content of the fluorine-modified polyurethane dispersion is 38-42%, the pH value is 7.0-9.0, the viscosity is 50-800 mPa·s, the trade name is only U XP 2750; the defoaming agent is a polydimethylsiloxane emulsion, the viscosity is 350-550 cSt, the specific gravity is 0.96-0.98; the leveling agent is a polyether-modified polysiloxane copolymer, the density is 1.01-1.02 g / cm 3 ; the wetting agent is sodium dodecyl benzene sulfonate, the active substance content is ≥ 92%, the pH value is 6.0-8.0; the film-forming aid is dipropylene glycol butyl ether, the boiling point is 230-232℃, the flash point is 100-102℃; the thickening agent is hydroxyethyl cellulose, the 2% aqueous solution viscosity is 3400-5000 mPa·s, the pH value is 6.0-8.5; the mildew-proof and bactericidal agent is an isothiazolinone mixture, the active ingredient content is 1.3-1.7%, the pH value is 2.0-4.0, the trade name is Kathon TM CG / ICP.

[0032] Example 1

[0033] The embodiment provides a high water resistance water-based paint for a ceramic tile surface, components and weight fractions of which are as follows:

[0034] 55 parts of an acrylic-silane modified copolymer emulsion, 3 parts of a nano-silica sol, 2 parts of a fluorine modified polyurethane dispersion, 0.1 part of a multi-walled carbon nanotube water dispersion, 5 parts of a bio-based epoxy resin emulsion, 0.2 part of a defoaming agent, 0.5 part of a leveling agent, 0.3 part of a wetting agent, 3 parts of a film-forming aid, 0.4 part of a thickening agent, 0.1 part of a mildew-proof fungicide, and 30 parts of deionized water.

[0035] The preparation method of the water-based paint comprises the following steps:

[0036] (1) First, an acrylic-silane modified copolymer emulsion is prepared. 150 g of deionized water is added to a four-necked flask, and heated to 75°C under nitrogen protection. 45 g of acrylic acid and 5 g of 3-methacryloxypropyltrimethoxysilane are mixed. 0.5 g of ammonium persulfate is dissolved in 20 g of deionized water. Under the condition of stirring at 300 rpm, the monomer mixture is slowly added to the reaction kettle within 2 hours, and the initiator solution is slowly added within 2.5 hours. After the reaction is completed, the temperature is kept at 75°C for 1 hour. After cooling to room temperature, the pH is adjusted to 7.0 with a 10% sodium hydroxide solution. Filtration through a 100-mesh screen gives the final product.

[0037] (2) Second, a multi-walled carbon nanotube water dispersion is prepared. 500 mL of deionized water is added to a beaker, and 1 g of sodium dodecylbenzenesulfonate is added as a dispersant and stirred until completely dissolved. 10 g of multi-walled carbon nanotube powder is slowly added at a stirring speed of 400 rpm. Ultrasonic dispersion is performed using a probe-type ultrasonic processor, with each treatment lasting 10 minutes, 5 minutes apart, for a total treatment time of 60 minutes. An ice bath is used to control the temperature at 20°C during the treatment. The dispersion is filtered through a 400-mesh screen, and large agglomerates are removed using a centrifuge (5000 rpm, 30 minutes), and the supernatant is taken as the final product.

[0038] (3) Then, a bio-based epoxy resin emulsion is prepared. 400 g of epoxy soybean oil (epoxy value 5.8%) is added to a four-necked flask. At 60°C, 20 g of polyethylene glycol monooleate and 5 g of polyethylene glycol monolaurate are slowly added as emulsifiers, with a stirring speed of 300 rpm. Under continuous stirring, 450 g of deionized water is slowly added dropwise, with a dropwise addition time of 30 minutes. Homogenization is performed using a high-speed shearing machine (10000 rpm) for 10 minutes. After cooling to room temperature, the mixture is filtered through a 200-mesh screen.

[0039] (4) Again, the preparation of water-based paint is carried out. Add 20 parts of deionized water to the reaction kettle, then add the multi-walled carbon nanotube water dispersion and nano-silica sol, and stir at a speed of 300 rpm for 10 minutes and 15 minutes respectively. Under stirring conditions, add the acrylic-silane modified copolymer emulsion and fluorine modified polyurethane dispersion in turn, the feeding time is 10 minutes, and continue to stir for 30 minutes after feeding is completed.

[0040] (5) Then, add the bio-based epoxy resin emulsion at 60°C, and then add the film forming aid, leveling agent, defoaming agent, wetting agent and mildew-proof fungicide in turn after cooling to 40°C, stir for 5 minutes after each component is added.

[0041] (6) Subsequently, add the thickening agent at 35°C, stir for 20 minutes, add deionized water, increase the stirring speed to 500 rpm, and continue to stir for 30 minutes.

[0042] (7) Finally, use a high-speed disperser to homogenize for 10 minutes at a speed of 3000 rpm. Vacuum degassing at -0.08 MPa for 15 minutes, filtered through a 5 μm precision filter, and filled into a clean, dry container under nitrogen protection, and sealed for storage.

[0043] In this example, the acrylic-silane modified copolymer emulsion enhances the chemical bonding ability of the coating to the surface of the ceramic tile by introducing silane groups, improving the adhesion of the coating. The nano-silica sol and the acrylic-silane modified copolymer form an interpenetrating network structure, while enhancing the hardness and chemical resistance of the coating. The fluorine modified polyurethane dispersion provides excellent hydrophobicity and self-cleaning ability, and synergizes with the bio-based epoxy resin emulsion to improve the stain resistance and easy cleaning of the coating while maintaining good flexibility. The multi-walled carbon nanotube water dispersion forms a three-dimensional network structure with other components, significantly improving the mechanical properties and scratch resistance of the coating. The bio-based epoxy resin emulsion not only improves the environmental friendliness of the coating, but also crosslinks with the acrylic-silane modified copolymer to form a semi-interpenetrating network structure, improving the chemical resistance and durability of the coating.

[0044] Example 2

[0045] This example provides a high adhesion water-based paint for marble surface, the components and weight fractions are as follows:

[0046] Acrylic-silane modified copolymer emulsion 65 parts, nano-silica sol 5.5 parts, fluorine modified polyurethane dispersion 4 parts, multi-walled carbon nanotube water dispersion 0.3 parts, bio-based epoxy resin emulsion 7.5 parts, defoaming agent 0.4 parts, leveling agent 0.75 parts, wetting agent 0.45 parts, film forming aid 5.5 parts, thickening agent 0.8 parts, mildew-proof fungicide 0.15 parts, deionized water 25 parts.

[0047] The method for preparing the aqueous coating includes the following steps:

[0048] (1) First, prepare the acrylic-silane modified copolymer emulsion. Add 165 g of deionized water in a four-necked flask and heat to 77.5°C under nitrogen protection. Mix 50 g of acrylic acid and 7.5 g of 3-methacryloxypropyl trimethoxysilane. Dissolve 0.75 g of ammonium persulfate in 25 g of deionized water. Under the condition of stirring at 350 rpm, slowly drop the monomer mixture into the reaction kettle within 2.5 hours, while slowly dropping the initiator solution within 3 hours. After the reaction is completed, keep the temperature at 77.5°C for 1 hour. Cool to room temperature and adjust the pH to 7.5 with 10% sodium hydroxide solution. Filter through a 100 mesh screen to obtain the final product.

[0049] (2) Second, prepare the multi-walled carbon nanotube aqueous dispersion. Add 550 mL of deionized water in a beaker and add 1.5 g of sodium dodecyl benzene sulfonate as a dispersant and stir until completely dissolved. Slowly add 15 g of multi-walled carbon nanotube powder with a stirring speed of 450 rpm. Use a probe-type ultrasonic processor for ultrasonic dispersion, 10 minutes each time, with 5 minutes interval, and the total processing time is 75 minutes, and an ice bath is used to control the temperature at 22.5°C during the processing. Filter the dispersion through a 400 mesh screen and use a centrifuge (5000 rpm, 30 minutes) to remove large agglomerates and take the supernatant as the final product.

[0050] (3) Then, prepare the bio-based epoxy resin emulsion. Add 425 g of epoxy soybean oil (epoxy value 6.0%) in a four-necked flask. At 62.5°C, slowly add 22.5 g of polyethylene glycol monooleate and 6.5 g of polyethylene glycol monolaurate as emulsifiers, with a stirring speed of 350 rpm. Under continuous stirring, slowly drop 475 g of deionized water, with a dropping time of 35 minutes. Use a high-speed shearing machine (11000 rpm) to homogenize for 12.5 minutes. Cool to room temperature and filter through a 200 mesh screen.

[0051] (4) Again, prepare the aqueous coating. Add 25 parts of deionized water in the reaction kettle, then add the multi-walled carbon nanotube aqueous dispersion and nano-silica sol, with a stirring speed of 350 rpm, and stir for 10 minutes and 15 minutes respectively. Under stirring conditions, add the acrylic-silane modified copolymer emulsion and the fluorine-modified polyurethane dispersion in sequence, with a feeding time of 12.5 minutes for each. After the feeding is completed, continue stirring for 30 minutes.

[0052] (5) Then, add the bio-based epoxy resin emulsion at 62.5°C, and then add the film-forming aids, leveling agents, defoaming agents, wetting agents and mildew-proof fungicides in sequence after cooling to 42.5°C, with a stirring time of 7.5 minutes for each component after addition.

[0053] (6) Subsequently, a thickening agent was added at 37.5°C, stirring was carried out for 20 minutes, deionized water was added, the stirring speed was increased to 550 rpm, and stirring was continued for 30 minutes.

[0054] (7) Finally, homogenization was carried out using a high-speed disperser for 12.5 minutes at a speed of 3500 rpm. Vacuum degassing was carried out at -0.08 MPa for 17.5 minutes, filtration was carried out through a 5-μm precision filter, and filling was carried out into a clean, dry container under nitrogen protection, and the container was sealed and stored.

[0055] In this embodiment, the content of the acrylic-silane modified copolymer emulsion was increased, further strengthening the chemical bonding ability of the coating to the marble surface, and significantly improving the adhesion of the coating. At the same time, the amount of nano-silica sol and multi-walled carbon nanotube water dispersion was increased, enhancing the hardness, wear resistance and scratch resistance of the coating. The amount of fluorine-modified polyurethane dispersion and bio-based epoxy resin emulsion was also increased, while maintaining good flexibility, further improving the stain resistance, easy cleaning and durability of the coating.

[0056] Example 3

[0057] This embodiment provides a high-chemical-resistance water-based paint for a stone surface, the components and weight fractions of which are as follows:

[0058] Acrylic-silane modified copolymer emulsion 70 parts, nano-silica sol 6.5 parts, fluorine-modified polyurethane dispersion 5 parts, multi-walled carbon nanotube water dispersion 0.4 parts, bio-based epoxy resin emulsion 8.5 parts, defoaming agent 0.5 parts, leveling agent 0.85 parts, wetting agent 0.5 parts, film-forming aid 6.5 parts, thickening agent 1 part, mildewcide 0.18 parts, deionized water 24 parts.

[0059] The preparation method of the water-based paint comprises the following steps:

[0060] (1) First, an acrylic-silane modified copolymer emulsion was prepared. 172.5 g of deionized water was added to a four-necked flask, and the temperature was raised to 78.5°C under nitrogen protection. 52.5 g of acrylic acid and 8.75 g of 3-methacryloyloxypropyltrimethoxysilane were mixed. 0.875 g of ammonium persulfate was dissolved in 27.5 g of deionized water. Under stirring conditions at 375 rpm, the monomer mixture was slowly added to the reaction kettle over a period of 2.75 hours, while the initiator solution was slowly added over a period of 3.25 hours. After the reaction was completed, the temperature was maintained at 78.5°C for 1 hour. After cooling to room temperature, the pH was adjusted to 7.75 with a 10% sodium hydroxide solution. Filtration was carried out through a 100-mesh screen to obtain the final product.

[0061] (2) Second, prepare the multi-walled carbon nanotube water dispersion. Add 575 mL of deionized water in a beaker, add 1.75 g of sodium dodecyl benzene sulfonate as a dispersant, and stir until completely dissolved. Slowly add 17.5 g of multi-walled carbon nanotube powder, with a stirring speed of 475 rpm. Use a probe-type ultrasonic processor for ultrasonic dispersion, 10 minutes each time, with a 5-minute interval, for a total processing time of 82.5 minutes, and use an ice bath to control the temperature at 23.75°C during processing. Filter the dispersion through a 400-mesh screen, remove large agglomerates using a centrifuge (5000 rpm, 30 minutes), and take the supernatant as the final product.

[0062] (3) Then, prepare the bio-based epoxy resin emulsion. Add 437.5 g of epoxy soybean oil (epoxy value 6.1%) in a four-necked flask. At 63.75°C, slowly add 23.75 g of polyethylene glycol monooleate and 7.25 g of polyethylene glycol monolaurate as emulsifiers, with a stirring speed of 375 rpm. Under continuous stirring, slowly add 487.5 g of deionized water dropwise, with a dropwise addition time of 37.5 minutes. Homogenize for 13.75 minutes using a high-speed shearing machine (11500 rpm). Cool to room temperature and filter through a 200-mesh screen.

[0063] (4) Again, prepare the water-based paint. Add 27.5 parts of deionized water in a reaction kettle, then add the multi-walled carbon nanotube water dispersion and nano-silica sol, with a stirring speed of 375 rpm, and stir for 10 minutes and 15 minutes, respectively. Under stirring conditions, sequentially add the acrylic-silane modified copolymer emulsion and the fluorine-modified polyurethane dispersion, with a feeding time of 13.75 minutes for each, and continue stirring for 30 minutes after feeding is complete.

[0064] (5) Next, add the bio-based epoxy resin emulsion at 63.75°C, and then sequentially add the film-forming aid, leveling agent, defoaming agent, wetting agent, and mildew-proof fungicide after cooling to 43.75°C, with a stirring time of 8.75 minutes for each component after addition.

[0065] (6) Subsequently, add the thickening agent at 38.75°C, stir for 20 minutes, add deionized water, increase the stirring speed to 575 rpm, and continue stirring for 30 minutes.

[0066] (7) Finally, homogenize using a high-speed dispersing machine for 13.75 minutes at a speed of 3750 rpm. Vacuum degassing at -0.08 MPa for 18.75 minutes, filter through a 5-μm precision filter, and fill into a clean, dry container under nitrogen protection, and store in a sealed manner.

[0067] In this embodiment, the content of acrylic-silane modified copolymer emulsion and bio-based epoxy resin emulsion is further increased, which significantly improves the chemical resistance of the coating. The amount of nano-silica sol and multi-walled carbon nanotube water dispersion is also increased accordingly, which strengthens the hardness and wear resistance of the coating. The amount of fluorine-modified polyurethane dispersion is increased, which further enhances the hydrophobicity and self-cleaning ability of the coating. This formulation is particularly suitable for stone plate surfaces and can provide excellent chemical resistance and durability.

[0068] Example 4

[0069] This embodiment provides a multifunctional water-based coating suitable for ceramic tiles, marble and stone plates, the components and weight fractions are as follows:

[0070] Acrylic-silane modified copolymer emulsion 75 parts, nano-silica sol 8 parts, fluorine-modified polyurethane dispersion 6 parts, multi-walled carbon nanotube water dispersion 0.5 parts, bio-based epoxy resin emulsion 10 parts, defoamer 0.6 parts, leveling agent 1 part, wetting agent 0.6 parts, film-forming aid 8 parts, thickening agent 1.2 parts, mildewcide 0.2 parts, deionized water 20 parts.

[0071] The preparation method of the water-based coating includes the following steps:

[0072] (1) First, prepare the acrylic-silane modified copolymer emulsion. Add 180g deionized water in a four-necked flask and heat to 80°C under nitrogen protection. Mix 55g acrylic acid and 10g 3-methacryloyloxypropyltrimethoxysilane. Dissolve 1g ammonium persulfate in 30g deionized water. Under the condition of stirring at 400rpm, slowly add the monomer mixture into the reaction kettle within 3 hours, and slowly add the initiator solution within 3.5 hours. After the reaction is completed, keep the temperature at 80°C for 1 hour. Cool to room temperature, adjust the pH to 8.0 with 10% sodium hydroxide solution. Filter through a 100 mesh screen to obtain the final product.

[0073] (2) Second, prepare the multi-walled carbon nanotube water dispersion. Add 600mL deionized water in a beaker, add 2g sodium dodecylbenzenesulfonate as a dispersant and stir until completely dissolved. Slowly add 20g multi-walled carbon nanotube powder with a stirring speed of 500rpm. Use a probe-type ultrasonic processor for ultrasonic dispersion, each treatment for 10 minutes, with an interval of 5 minutes, the total treatment time is 90 minutes, and an ice bath is used to control the temperature at 25°C during the treatment. Filter the dispersion through a 400 mesh screen, remove the large agglomerates using a centrifuge (5000rpm, 30 minutes), and take the supernatant as the final product.

[0074] (3) Then, the bio-based epoxy resin emulsion was prepared. In a four-necked flask, 450 g of epoxy soybean oil (epoxy value 6.2%) was added. At 65 °C, 25 g of polyethylene glycol monooleate and 8 g of polyethylene glycol monolaurate were slowly added as emulsifiers, with a stirring speed of 400 rpm. Under continuous stirring, 500 g of deionized water was slowly added dropwise, with a dropwise addition time of 40 minutes. Homogenization was performed using a high-speed shear machine (12000 rpm) for 15 minutes. After cooling to room temperature, filtration was performed through a 200-mesh screen.

[0075] (4) Again, the preparation of the water-based paint was performed. In a reaction kettle, 30 parts of deionized water were added, followed by the addition of a multi-walled carbon nanotube water dispersion and a nano-silica sol, with a stirring speed of 400 rpm, and stirring for 10 minutes and 15 minutes, respectively. Under stirring conditions, an acrylic-silane modified copolymer emulsion and a fluorine-modified polyurethane dispersion were sequentially added, with an addition time of 15 minutes for each. After the addition was completed, stirring was continued for 30 minutes.

[0076] (5) Next, the bio-based epoxy resin emulsion was added at 65 °C, and after the temperature was lowered to 45 °C, film-forming aids, leveling agents, defoaming agents, wetting agents, and mildewcides were sequentially added, with stirring for 10 minutes after each component was added.

[0077] (6) Subsequently, a thickening agent was added at 40 °C, with stirring for 20 minutes, deionized water was added, the stirring speed was increased to 600 rpm, and stirring was continued for 30 minutes.

[0078] (7) Finally, homogenization was performed using a high-speed dispersion machine for 15 minutes, at a speed of 4000 rpm. Vacuum degassing was performed at -0.08 MPa for 20 minutes, filtration was performed through a 5-μm precision filter, and the product was filled into a clean, dry container under nitrogen protection, and stored after sealing.

[0079] In this example, the content of each component reached the highest level, aiming to provide a high-performance water-based paint suitable for the surfaces of various inorganic substrates. The high content of the acrylic-silane modified copolymer emulsion ensured excellent adhesion, and the maximum amount of the nano-silica sol and the multi-walled carbon nanotube water dispersion provided excellent hardness, wear resistance, and scratch resistance. The high content of the fluorine-modified polyurethane dispersion and the bio-based epoxy resin emulsion endowed the coating with excellent hydrophobicity, self-cleaning ability, flexibility, and chemical resistance. This formulation reached the best level in various performance indicators, and was suitable for occasions with extremely high requirements for coating performance.

[0080] Comparative Example 1: Water-based paint lacking an acrylic-silane modified copolymer emulsion

[0081] This comparative example aimed to verify the importance of the acrylic-silane modified copolymer emulsion for the performance of the paint, especially its effect on adhesion. This comparative example was compared with Example 1, and the components and weight fractions were as follows:

[0082] Common acrylic emulsion 55 parts, nano-silica sol 3 parts, fluorine-modified polyurethane dispersion 2 parts, multi-walled carbon nanotube aqueous dispersion 0.1 part, bio-based epoxy resin emulsion 5 parts, defoaming agent 0.2 part, leveling agent 0.5 part, wetting agent 0.3 part, film-forming aid 3 parts, thickening agent 0.4 part, mildewcide 0.1 part, deionized water 20 parts.

[0083] The preparation method of the water-based paint is basically the same as that of Example 1, except that the common acrylic emulsion is used instead of the acrylic-silane modified copolymer emulsion. The preparation method of the common acrylic emulsion is as follows:

[0084] In a four-necked flask, 150 g of deionized water was added and heated to 75°C under nitrogen protection. 50 g of acrylic acid was added. 0.5 g of ammonium persulfate was dissolved in 20 g of deionized water. Under the condition of stirring at 300 rpm, the monomers were slowly added into the reaction kettle within 2 hours, and the initiator solution was slowly added within 2.5 hours. After the reaction was completed, the temperature was kept at 75°C for 1 hour. Cool to room temperature, adjust the pH to 7.0 with 10% sodium hydroxide solution. Filter through a 100 mesh screen to obtain the final product.

[0085] Through comparative testing, it is found that the paint prepared in this comparative example has a significant deficiency in adhesion compared to Example 1. This is because the lack of silane groups cannot form strong chemical bonds with inorganic substrates. In addition, the water resistance and chemical resistance of the coating are also decreased, which indicates that the acrylic-silane modified copolymer emulsion plays a key role in improving the overall performance of the coating.

[0086] Comparative Example 2: Water-based paint without multi-walled carbon nanotube aqueous dispersion

[0087] This comparative example aims to verify the influence of multi-walled carbon nanotube aqueous dispersion on the mechanical properties of the paint. This comparative example is compared with Example 2, and its components and weight fractions are as follows:

[0088] Acrylic-silane modified copolymer emulsion 65 parts, nano-silica sol 5.5 parts, fluorine-modified polyurethane dispersion 4 parts, bio-based epoxy resin emulsion 7.5 parts, defoaming agent 0.4 part, leveling agent 0.75 part, wetting agent 0.45 part, film-forming aid 5.5 part, thickening agent 0.8 part, mildewcide 0.15 part, deionized water 25 parts.

[0089] The preparation method of the water-based paint is basically the same as that of Example 2, except that the preparation and addition steps of the multi-walled carbon nanotube aqueous dispersion are omitted.

[0090] It was found through comparison tests that the coating prepared in this comparative example performed worse in scratch resistance and mechanical strength compared to Example 2. This is because multi-walled carbon nanotubes can form a three-dimensional network structure in the coating, significantly enhancing the mechanical properties of the coating. Without this component, the overall strength and wear resistance of the coating are both reduced, indicating that the multi-walled carbon nanotube aqueous dispersion plays an important role in improving the durability of the coating.

[0091] Comparative Example 3: Water-based coating using ordinary epoxy resin emulsion instead of bio-based epoxy resin emulsion

[0092] This comparative example aims to verify the influence of bio-based epoxy resin emulsion on the environmental friendliness and performance of the coating. This comparative example is compared with Example 3, and the components and weight fractions are as follows:

[0093] Acrylic-silane modified copolymer emulsion 70 parts, nano-silica sol 6.5 parts, fluorine-modified polyurethane dispersion 5 parts, multi-walled carbon nanotube aqueous dispersion 0.4 parts, ordinary epoxy resin emulsion 8.5 parts, defoamer 0.5 parts, leveling agent 0.85 parts, wetting agent 0.5 parts, film-forming aid 6.5 parts, thickening agent 1 part, mildewcide 0.18 parts, deionized water 24 parts.

[0094] The preparation method of this water-based coating is basically the same as that of Example 3, except that ordinary epoxy resin emulsion is used instead of bio-based epoxy resin emulsion. The preparation method of ordinary epoxy resin emulsion is as follows:

[0095] In a four-necked flask, 425 g of bisphenol A type epoxy resin (epoxy value 0.52 eq / 100 g) was added. At 63.75°C, 23.75 g of polyethylene glycol monooleate and 7.25 g of polyethylene glycol monolaurate were slowly added as emulsifiers, with a stirring speed of 375 rpm. Under continuous stirring, 487.5 g of deionized water was slowly added dropwise, with a dropwise time of 37.5 minutes. Homogenization was performed using a high-speed shear machine (11500 rpm) for 13.75 minutes. After cooling to room temperature, it was filtered through a 200-mesh screen.

[0096] It was found through comparison tests that the coating prepared in this comparative example performed similarly in chemical resistance compared to Example 3, but had some shortcomings in environmental friendliness and flexibility. The use of bio-based epoxy resin not only improves the environmental friendliness of the coating, but also enhances the flexibility of the coating through its special molecular structure. This indicates that the bio-based epoxy resin emulsion plays an important role in balancing the performance and environmental requirements of the coating.

[0097] Comparative Example 4: Water-based coating without fluorine-modified polyurethane dispersion

[0098] This comparative example aims to verify the influence of fluorine-modified polyurethane dispersion on the hydrophobicity and self-cleaning ability of the coating. The components and weight fractions of this comparative example are as follows:

[0099] Acrylic-silane modified copolymer emulsion 75 parts, nano-silica sol 8 parts, multi-walled carbon nanotube aqueous dispersion 0.5 parts, bio-based epoxy resin emulsion 10 parts, defoamer 0.6 parts, leveling agent 1 part, wetting agent 0.6 parts, film-forming aid 8 parts, thickening agent 1.2 parts, mildewcide 0.2 parts, deionized water 20 parts.

[0100] The preparation method of this water-based coating is basically the same as that of Example 4, except that the step of adding fluorine-modified polyurethane dispersion is omitted.

[0101] Through comparative testing, it is found that the coating prepared in this comparative example performs significantly worse in terms of hydrophobicity and self-cleaning ability compared to Example 4. The contact angle of the coating is significantly reduced, and the resistance to stains also decreases. This indicates that fluorine-modified polyurethane dispersion plays a key role in providing excellent surface properties, and its synergistic effect with other components is crucial for achieving high-performance coatings.

[0102] Comparative Example 5: Water-based coating using ordinary silica powder instead of nano-silica sol

[0103] This comparative example aims to verify the influence of nano-silica sol on the hardness and wear resistance of the coating. The components and weight fractions of this comparative example are as follows:

[0104] Acrylic-silane modified copolymer emulsion 55 parts, ordinary silica powder 3 parts, fluorine-modified polyurethane dispersion 2 parts, multi-walled carbon nanotube aqueous dispersion 0.1 parts, bio-based epoxy resin emulsion 5 parts, defoamer 0.2 parts, leveling agent 0.5 parts, wetting agent 0.3 parts, film-forming aid 3 parts, thickening agent 0.4 parts, mildewcide 0.1 parts, deionized water 30 parts.

[0105] The preparation method of this water-based coating is basically the same as that of Example 1, except that ordinary silica powder is used instead of nano-silica sol, and the powder is directly added during the preparation process.

[0106] Through comparative testing, it is found that the coating prepared in this comparative example performs worse in terms of hardness and wear resistance compared to Example 1. This is because ordinary silica powder is difficult to disperse uniformly in the coating, and cannot form an effective interpenetrating network structure with the acrylic-silane modified copolymer. While nano-silica sol can fully combine with other components at the molecular level, significantly enhancing the overall performance of the coating. This indicates that nano-silica sol plays an important role in improving the hardness and wear resistance of the coating.

[0107] Comparative Example 6: Water-based paint without film-forming aid

[0108] This comparative example aims to verify the influence of the film-forming aid on the film-forming performance and low-temperature application performance of the paint. The components and weight fractions of this comparative example are as follows:

[0109] 65 parts of acrylic-silane modified copolymer emulsion, 5.5 parts of nano-silica sol, 4 parts of fluorine-modified polyurethane dispersion, 0.3 parts of multi-walled carbon nanotube aqueous dispersion, 7.5 parts of bio-based epoxy resin emulsion, 0.4 parts of defoamer, 0.75 parts of leveling agent, 0.45 parts of wetting agent, 0.8 parts of thickening agent, 0.15 parts of mildewcide, and 25 parts of deionized water.

[0110] The preparation method of this water-based paint is basically the same as that of Example 2, except that the step of adding the film-forming aid is omitted.

[0111] Through comparative testing, it is found that the film-forming performance of the paint prepared in this comparative example is significantly decreased under low-temperature conditions compared with Example 2. In an environment below 5℃, the coating layer shows cracking and whitening phenomena, which affects the overall performance and appearance of the coating layer. This indicates that the film-forming aid plays a key role in improving the low-temperature film-forming performance of the paint, especially in cold seasons or low-temperature environments.

[0112] Through these six comparative examples, the influence of each key component of the present application on the performance of the paint is comprehensively verified. The results show that there is a significant synergistic effect between the acrylic-silane modified copolymer emulsion, the multi-walled carbon nanotube aqueous dispersion, the bio-based epoxy resin emulsion, the fluorine-modified polyurethane dispersion, the nano-silica sol, and the film-forming aid. This synergistic effect not only improves the adhesion, water resistance, chemical resistance, scratch resistance, and mechanical strength of the paint, but also improves the environmental friendliness, flexibility, hydrophobicity, and self-cleaning ability of the coating layer. At the same time, the formulation of the present application also ensures the good film-forming performance of the paint under low-temperature conditions. These results fully demonstrate the innovation and superiority of the present application, providing a new idea and direction for the development of high-performance water-based paints.

[0113] To comprehensively evaluate the performance of the water-based paint of the present application, the following test items are designed:

[0114] 1. Adhesion test (ASTM D4541)

[0115] 2. Water resistance test (ASTM D870)

[0116] 3. Chemical resistance test (ASTM D1308)

[0117] 4. Abrasion resistance test (ASTM D4060)

[0118] 5. Scratch resistance test (ISO 1518-1)

[0119] 6. Hydrophobicity test (Contact angle measurement)

[0120] 7. Self-cleaning ability test (Stain removal efficiency)

[0121] 8. Low temperature film formation performance test (ASTM D2243)

[0122] 9. UV aging resistance test (ASTM G154)

[0123] 10. Environmental friendliness evaluation (VOC content determination, EPA method 24)

[0124] Test method summary:

[0125] 1. Adhesion test: Use a pull-off adhesion tester to measure the force required to separate the coating from the substrate.

[0126] 2. Water resistance test: Soak the coating in 25°C deionized water for 168 hours and observe for blistering, peeling, etc.

[0127] 3. Chemical resistance test: Drop 10% NaOH and 10% H2SO4 solutions on the coating surface for 48 hours and evaluate the coating's corrosion resistance.

[0128] 4. Abrasion resistance test: Use a Taber abrasion tester with CS-17 wheels and a 1000g load to test the mass loss after 1000 cycles.

[0129] 5. Scratch resistance test: Use a scratch tester to determine the minimum load at which visible scratches appear on the coating surface.

[0130] 6. Hydrophobicity test: Use a contact angle meter to measure the contact angle of a water droplet on the coating surface.

[0131] 7. Self-cleaning ability test: Drop standard stains (such as coffee, red ink) on the coating surface and evaluate the degree of residual stains after rinsing with clean water.

[0132] 8. Low temperature film formation performance test: Apply and dry the coating at 5°C for 24 hours and observe for cracking, whitening, etc.

[0133] 9. UV aging resistance test: Use a QUV accelerated aging tester to evaluate the performance changes of the coating after 1000 hours of UV light exposure.

[0134] 10. Environmental friendliness evaluation: Determine the volatile organic compound (VOC) content in the paint.

[0135] Test results:

[0136] Table 1: Performance test results of each example and comparative example

[0137]

[0138] Note: Water resistance, alkali resistance, acid resistance level: 1st (excellent) - 5th (very poor); self-cleaning ability is stain removal rate; UV aging resistance is color difference value ΔE.

[0139] From the test results, the following conclusions can be drawn:

[0140] 1. Best example: Example 4 exhibits the most excellent comprehensive performance, especially in adhesion, wear resistance, scratch resistance, hydrophobicity and self-cleaning ability. This is mainly due to the best ratio and synergistic effect of each component.

[0141] 2. Innovation points and effects:

[0142] a) Acrylic-silane modified copolymer emulsion: The results of Comparative Example 1 clearly show that this component significantly improves the adhesion (4.0 MPa vs 2.1 MPa) and water resistance of the coating. This is due to the strong chemical bonding of silane groups with inorganic substrates, as well as the increased crosslinking density of the coating.

[0143] b) Multi-walled carbon nanotube aqueous dispersion: The results of Comparative Example 2 show that this component significantly improves the wear resistance (10 mg vs 25 mg) and scratch resistance (10 N vs 5 N) of the coating. This is because carbon nanotubes form a three-dimensional network structure in the coating, enhancing the mechanical strength of the coating.

[0144] c) Bio-based epoxy resin emulsion: The results of Comparative Example 3 show that this component not only reduces the VOC content (32 g / L vs 40 g / L), but also improves the flexibility and chemical resistance of the coating. This is due to the special molecular structure of the bio-based epoxy resin, which provides a better crosslinking network.

[0145] d) Fluorine-modified polyurethane dispersion: The results of Comparative Example 4 show that this component significantly improves the hydrophobicity (contact angle 120° vs 98°) and self-cleaning ability (98% vs 80%) of the coating. This is because the fluorinated component forms a low surface energy structure on the surface of the coating.

[0146] e) Nano-silica sol: The results of Comparative Example 5 show that this component significantly improves the hardness and wear resistance (10 mg vs 30 mg) of the coating. This is because nano-silica forms an effective interpenetrating network structure with the polymer matrix.

[0147] f) Film forming aids: The results of Comparative Example 6 show that this component is crucial for low-temperature film forming properties, ensuring the application performance of the coating in low-temperature environments.

[0148] 3. Unexpected technical effects:

[0149] a) Superb comprehensive performance: The coating of the present application not only maintains high adhesion but also achieves excellent water resistance, chemical resistance, wear resistance, and scratch resistance. This comprehensive performance improvement is the result of the synergistic effect of various components, far exceeding the effect of single modification.

[0150] b) Excellent self-cleaning ability: The coating exhibits a 98% stain removal rate, far exceeding traditional water-based coatings. This is the result of the synergistic effect of fluorine-modified polyurethane dispersion and other components, forming a unique surface microstructure.

[0151] c) Excellent UV aging resistance: The ΔE value is only 0.6, indicating that the coating has strong UV resistance. This may be due to the synergistic effect of multi-walled carbon nanotubes and nano-silica, forming an effective UV shielding layer.

[0152] d) Perfect combination of environmental friendliness and high performance: While achieving excellent performance, the VOC content remains at a low level (35 g / L). This breaks the traditional concept that high-performance coatings must be accompanied by high VOC content.

[0153] e) Broad applicability: The coating performs well on various inorganic substrates such as ceramic tiles, marbles, and stone slabs. This broad applicability is the result of the precise matching of various components, providing great convenience for practical applications.

[0154] The present application achieves synergistic effects among various components through a carefully designed multi-component system, not only performing excellently in adhesion, water resistance, chemical resistance, and other conventional indicators, but also making breakthroughs in self-cleaning ability, UV aging resistance, and environmental friendliness.

[0155] The above description is only an example of the present application and is not intended to limit the present application. For those skilled in the art, the present application can have various modifications and changes. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present application shall be included in the scope of the claims of the present application.

Claims

1. A water-based paint for tiles, marble, and slate, characterized in that: The water-based coating comprises the following components in parts by weight: 55-75 parts of acrylic acid-silane modified copolymer emulsion; 3-8 parts of nano-silica sol; 2-6 parts of fluorine-modified polyurethane dispersion; 0.1-0.5 parts of multi-walled carbon nanotube aqueous dispersion; 5-10 parts of bio-based epoxy resin emulsion; 0.2-0.6 parts of defoaming agent; 0.5-1 parts of leveling agent; 0.3-0.6 parts of wetting agent; 3-8 parts of film-forming aid; 0.4-1.2 parts of thickener; 0.1-0.2 parts of mildew-proofing and fungicide; and 20-30 parts of deionized water.

2. The water-based paint according to claim 1, characterized in that The preparation method of the acrylic acid-silane modified copolymer emulsion comprises the following steps: (1) adding 150-180 g of deionized water into a four-necked flask and heating the flask to 75-80° C. under nitrogen protection; (2) mixing 45-55 g of acrylic acid and 5-10 g of 3-methacryloxypropyltrimethoxysilane; (3) dissolving 0.5-1.0 g of ammonium persulfate in 20-30 g of deionized water; (4) slowly dropping the monomer mixture of step (2) into a reactor over 2-3 hours under stirring at 300-400 rpm; (5) simultaneously, slowly dropping the initiator solution of step (3) over 2.5-3.5 hours; (6) after the reaction is completed, keeping the flask at 75-80° C. for 1 hour; (7) cooling the flask to room temperature and adjusting the pH to 7.0-8.0 with 10% sodium hydroxide solution; and (8) filtering the flask through a 100-mesh sieve to obtain the final product.

3. The water-based paint according to claim 1, characterized in that The preparation method of the multi-walled carbon nanotube aqueous dispersion comprises the following steps: (1) adding 500-600 mL of deionized water into a beaker; (2) adding 1-2 g of sodium dodecylbenzenesulfonate as a dispersant and stirring until completely dissolved; (3) slowly adding 10-20 g of multi-walled carbon nanotube powder at a stirring speed of 400-500 rpm; (4) using a probe-type ultrasonic processor for ultrasonic dispersion, each treatment for 10 minutes, with an interval of 5 minutes, and a total treatment time of 60-90 minutes, and using an ice bath to control the temperature at 20-25° C. during the treatment; (5) filtering the dispersion through a 400-mesh screen; (6) using a centrifuge (5000 rpm, 30 minutes) to remove large agglomerates; and (7) taking the supernatant as the final product.

4. The water-based paint according to claim 1, characterized in that The preparation method of the bio-based epoxy resin emulsion comprises the following steps: (1) adding 400-450 g of epoxidized soybean oil (epoxy value 5.8-6.2%) into a four-necked flask; (2) slowly adding 20-25 g of polyethylene glycol monooleate and 5-8 g of polyethylene glycol monolaurate as emulsifiers at 60-65° C., with a stirring speed of 300-400 rpm; (3) slowly adding 450-500 g of deionized water dropwise under continuous stirring for 30-40 minutes; (4) homogenizing the mixture using a high-speed shearing machine (10,000-12,000 rpm) for 10-15 minutes; and (5) cooling the mixture to room temperature and filtering the mixture through a 200-mesh sieve.

5. The water-based paint according to claim 1, characterized in that: The nano-silica sol has a particle size of 20-25 nm, a solid content of 49-51%, and a pH value of 8.5-9.5; the fluorine-modified polyurethane dispersion has a solid content of 38-42%, a pH value of 7.0-9.0, and a viscosity of 50-800 mPa·s; the defoaming agent is a polydimethylsiloxane emulsion with a viscosity of 350-550 cSt and a specific gravity of 0.96-0.98; the leveling agent is a polyether-modified polysiloxane copolymer with a density of 1.01-1.02 g / cm 3 The wetting agent is sodium dodecylbenzenesulfonate, with an active substance content of ≥92% and a pH value of 6.0-8.0; the film-forming aid is dipropylene glycol butyl ether, with a boiling point of 230-232°C and a flash point of 100-102°C; the thickener is hydroxyethyl cellulose, with a 2% aqueous solution viscosity of 3400-5000mPa·s and a pH value of 6.0-8.5; the mildew and fungicide is an isothiazolinone mixture, with an active ingredient content of 1.3-1.7% and a pH value of 2.0-4.

0.

6. A method for preparing a water-based coating according to any one of claims 1 to 5, characterized in that: The following steps are involved: (1) Pre-dispersion: Add 20-30 parts of deionized water to the reactor, then add the multi-walled carbon nanotube aqueous dispersion and nano-silica sol, stirring at a speed of 300-400 rpm, stirring for 10 minutes and 15 minutes respectively; (2) Main emulsion addition: Add the acrylic acid-silane modified copolymer emulsion and fluorine-modified polyurethane dispersion in sequence under stirring conditions, the addition time is 10-15 minutes, and continue stirring for 30 minutes after the addition is completed; (3) Functional component addition: at 60-65 ° C Add bio-based epoxy resin emulsion at 35-40°C, cool to 40-45°C, add film-forming agent, leveling agent, defoamer, wetting agent and mildew-proof fungicide in sequence; (4) Adjustment and homogenization: add thickener at 35-40°C, add deionized water, use high-speed disperser to homogenize for 10-15 minutes, the speed is 3000-4000rpm; (5) Vacuum degassing and filling: vacuum degassing at -0.08MPa for 15-20 minutes, filter through 5μm precision filter, and fill under nitrogen protection.

7. The preparation method according to claim 6, characterized in that In step (3), the order of adding the components is: first add the film-forming aid and stir for 5-10 minutes; then add the leveling agent and stir for 5-10 minutes; then add the defoamer and stir for 5-10 minutes; then add the wetting agent and stir for 5-10 minutes; finally add the mildew inhibitor and stir for 10 minutes.

8. The preparation method according to claim 6, characterized in that In the step (4), the thickener is added and stirred for 20 minutes, then deionized water is added, the stirring speed is increased to 500-600 rpm, and stirring is continued for 30 minutes.

9. The preparation method according to claim 6, characterized in that In the step (5), the filtered coating is filled into a clean and dry container under nitrogen protection and sealed for storage.

10. The water-based paint according to any one of claims 1 to 9, characterized in that: The water-based paint has a solid content of 50-55%, a pH value of 7.5-8.5, a viscosity of 2500-3500 mPa·s, and a minimum film-forming temperature of less than 0°C.

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